Reliability, Validity, Modification and Expansion of the Chinese Version of the Disease-Specific Anxiety Questionnaire for Chronic Obstructive Pulmonary Disease.

Purpose: To translate a disease-specific anxiety questionnaire on chronic obstructive pulmonary disease (COPD) and test its reliability and validity in China. Patients and Methods: The German version of the revised COPD Anxiety Questionnaire (CAF-R) was initially validated using step-by-step translation, back-translation, and cross-cultural adaptation. The reliability and validity of the Chinese version of the CAF-R (CAF-R-CN) were tested among 448 patients with COPD (mean age =71.42±9.33 years, 17.2% female) from four medical institutions in Suzhou, Jiangsu Province, using convenience sampling, from April 2022 to June 2023. Results: The CAF-R-CN included six dimensions with a total of 25 items. The item-level content validity index was 0.860-1.000; the scale-level content validity index was 0.920. The structural validity χ2/df was 2.326, the root mean square error of approximation was 0.077, the comparative fit index was 0.924, and the Tucker-Lewis index was 0.912. The six-dimensional internal consistency index Cronbach's α coefficient was 0.696-0.910, and the test-retest reliability was 0.949. An optimal cut-off score of 50.5 was selected with a sensitivity of 0.786 and specificity of 0.870. Conclusion: The CAF-R-CN had satisfactory reliability and validity and can be used to identify and assess anxiety in COPD patients with a Chinese cultural background.

Association Between Anthropometric Indices and Skeletal-Muscle Atrophy in Chinese Patients with Stable Chronic Obstructive Pulmonary Disease: A Cross-Sectional Study.

Purpose: Anthropometric indices are simple indicators of patient nutritional status. However, the association between these indices and skeletal-muscle atrophy in patients with stable chronic obstructive pulmonary disease (COPD) has not been fully investigated. In this study, we evaluated this association. Patients and Methods: We recruited 123 outpatients with stable COPD from a general hospital in China from 2020 to 2021. We recorded their demographic characteristics, including age, sex, course of illness, dyspnea score, body mass index (BMI), force expiratory volume in 1 second (FEV1), forced vital capacity (FVC), smoking status, and severity grading. In addition, patients' anthropometric indices, including fat-free mass index (FFMI) and appendicular skeletal-muscle mass index (ASMI), were measured using a body composition analyzer, and measurements were taken of the triceps skinfold (TSF), midarm circumference (MAC), and calf circumference (CC). We drew and analyzed a receiver operating characteristic (ROC) curve to identify the best intercept point value for the assessment of skeletal-muscle atrophy. Results: The TSF, MAC, CC, FFMI, and ASMI of COPD patients were 1.08 ± 0.44 cm, 26.39 ± 2.92 cm, 34.5 ± 3.06 cm, 17.49 ± 1.86 kg/m2, and 8.17 ± 0.90 kg/m2, respectively. These anthropometric indices had a significant positive correlation with skeletal-muscle mass (correlation values, 0.481-0.820). CC was strongly correlated with both FFMI and ASMI. The ROC curve showed an area-under-the-curve (AUC) value of 0.873-0.959. Conclusion: Anthropometric indices were correlated with skeletal-muscle mass. CC showed the best diagnostic value in COPD patients, suggesting its effectiveness as a simple method for assessing skeletal-muscle atrophy and identifying patients with a noticeable reduction in muscle mass. Such patients require early, multidisciplinary intervention.